Opal in its host rock. Opals are a form of hydrated silica glass. They are not truly crystalline,and are classified as mineraloids. Here the opal has taken on a botryoidal (grape-like) form and lacks the colour and lustre of the precious forms used in jewellery. This specimen is from Lolling,near Huttenberg,Austria | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Wiersma, Dirk |
Taille de l’image : | 5197 px × 3465 px |
Model Release : | Non requis |
Restrictions : | - |